When Clark (Tom Welling) rescues his classmate Eric (guest star Shawn Ashmore) from harm during an electrical storm, they are both struck by lightening, resulting in all of Clark's superpowers transferring to Eric. While Eric relishes his new life as "Superboy," Clark is torn between his happiness at finally being normal and his growing concern for the town's safety as Eric starts to abuse his powers. Meanwhile, Lex (Michael Rosenbaum) believes he finally has undeniable proof of Clark's superpowers and confronts him.
Kristin Kreuk, Michael Rosenbaum, Allison Mack, Sam Jones III, Eric Johnson, Annette O'Toole and John Schneider also star. Greg Beeman directed the episode written by Tim Schlattmann.

Both Clark and a classmate named Eric are struck by lightning when Eric is holding a piece of meteorite rock. The strike takes Clark's powers away and transfers them to Eric. As Eric gets used to his new powers, Clark has to deal with being a normal person for the first time, with all the advantages and disadvantages. Eric's domineering father wants to have him examined in Metropolis - in response, Eric goes on a rampage. Borrowing Lana's meteor-rock necklace, Clark confronts Eric at a power plant and manages to reverse the transfer. Meanwhile, Sir Harry Hardwick (Victoria's father, and rival of Lionel Luthor) and his daughter try to recruit Lex for their business in Metropolis and almost succeed in buying out LuthorCorp, but they find out that they were tricked by Lex.

Victoria: We could've been great together.
Lex: I plan on being great all by myself.

Lionel: Smallville is your test and now you are failing.

Jonathan: How are you holding up?
Clark: Considering my chores use to take me five minutes and now they take two hours, I'm alright.

Pete: Why are you grinning? We lost.
Clark: I know. Pretty cool, huh?

Chloe: I'm sorry, but I find geology even more pointless than algebra. I mean, I could just order these rocks online and have them delivered to my house vacuum-sealed.

Lex: You call sleeping with me business? I hate to think what that makes you.

Lex: Listen, I had no right to question your honesty. All I can do is plead temporary insanity and hope we can find a way to put this behind us.
Clark: Only temporary?

Clark: I hope all this attention doesn't go to his head. He needs to be careful.
Chloe: Well, you know what, Clark, the second you start throwing people thirty feet, I'll write nice things about you too.

Clark: You don't feel any differently about me now do you?
Martha: Clark, you're our son whether you can bench-press the tractor or not.

Jonathan: You know what they say: lightning never strikes twice in the same place. Look, my guess is that your powers aren't coming back.
Clark: Maybe being normal won't be so bad; I mean it works for you and Mom.
Mrs. Kent: Oh, thanks.

Pete: He's been acting weird lately.
Chloe: Well, okay, Clark's always acting weird, why don't you give me a gauge?

Roger: This could make one hell of a story.
Lex: No one's ever going know about this; and if this story is accidently leaked, you and I are going to have a serious trust issue.
Roger: (sarcastically) As opposed to the close, personal relationship we enjoy now.

Eric: Come on, Clark. If you had the power to do whatever you want, what would you do?
Clark: I'd stop people like you.

On a geological trip with Science Professor Summers, the kids are made to look for different types of rocks. Clark Kent and Pete Ross are left with finding quartz and meteor, and Clark, with his x-ray vision quickly finds the quartz. When the gang reassembles, Lana Lang is wearing her meteor necklace and Clark has to stay at a distance. Another kid, Eric Summers, the professor's son, has just found two pieces of meteor rock. He offers one to Holly, whom he has a crush on, but she thanks him and refuses since she already has one. At that moment, her boyfriend and football jock Brent confronts him for hitting on his girlfriend. Eric also gets grief from his dad who is harder on his son than on other students.

When all the students meet up in the bus to return to school, Eric is missing. Clark volunteers to find him. He finds Eric on a bridge, holding the piece of meteor rock, about to jump off, listening to "Fade" by Staind on his diskman. As Clark approaches to get Eric to step back, Eric trips and starts falling over the bridge. Clark catches his arm, but is finding it extremely hard to hold on due to the meteor rock in Eric's hand. At that moment, lightening strikes, and Clark's powers get transferred to Eric.

As Clark is getting used to his lack of powers, Eric is finding his various strengths. At breakfast, he apologizes to his parents for the trip's incident, but his father is still upset. As he goes to hit his son, Eric stops his arm, which freaks both his parents out. Later, Eric is watching his dream girl Holly with her boyfriend. At the same moment, Chloe Sullivan and Pete are walking down the street, and someone snatches Chloe's laptop. Eric uses his superspeed to catch up with the thief, and his superpower to stop the thief's knife. Eric then throws the thief across the street. Everyone, including Holly and Brent, witness the event, and Chloe thanks him profoundly. The following day, she writes an article about him, with the title Superboy, that Eric likes very much.

When Eric returns home, he finds his parents concerned, they want to take him to doctors to study him. Eric gets upset, claiming he is not a science experiment, assaults his father and runs out. Angry, he goes to school, where he hits on Holly. Brent goes to fight him, but the fight turns ugly, and Brent is thrown onto a table. Clark tries to intervene and is thrown over a car. Clark has a couple of broken ribs. Eric returns home, to find that his parents have called the cops. He escapes and runs to the bridge, attempting to jump off the bridge. But his powers have no limit, and he doesn't fall.. He flies back to the top of the bridge, where Clark has caught up with him. Clark has borrowed Lana's necklace, and tries to stop Eric with it. There is a confrontation, and at the same time, an electric shock transfers the powers back to Clark. Eric is taken to hospital.